BUG: Ceramic One daemon fails to start on testnet-clay due to an invalid default Ethereum RPC URL

[sphfaar]

Describe the bug
The Ceramic One daemon fails to start on testnet-clay due to an invalid default Ethereum RPC URL. The codebase uses https://gnosis-mainnet.public.blastapi.io, which is for Gnosis mainnet (not Chiado testnet) and has been deprecated by Blast API, resulting in a 403 error. This prevents the daemon from launching without manual RPC configuration.

To Reproduce
Steps to reproduce the behavior:

1. Set up Ceramic One via Docker Compose as per the docs (https://developers.ceramic.network/docs/protocol/ceramic-one/usage/installation#docker-compose).
2. Run docker-compose up -d.
3. Check container logs with docker logs <container_id>.
4. See the error: "No usable ethereum RPC configured for network testnet-clay".

Expected behavior
The daemon should start successfully.

Ceramic versions
Ceramic One: 0.57.0 (build: git:0a7b433-modified)

Machine, OS, browser information (please complete the following information):
Linux 6.17.9-arch1-1

Additional context

Relevant logs:

2025-11-28T17:27:10.117903Z  WARN ceramic_one: failed to create RPC client with url: 'https://gnosis-mainnet.public.blastapi.io': InvalidArgument("failed to retrieve chain ID: HTTP error 403 with body: {\n  \"jsonrpc\": \"2.0\",\n  \"id\": null,\n  \"error\": {\n    \"code\": -32000,\n    \"message\": \"Blast API is no longer available. Please update your integration to use Alchemy's API instead: https://alchemy.com\"\n  }\n}\n")
2025-11-28T17:27:10.117919Z ERROR ceramic_one: Error running command: No usable ethereum RPC configured for network testnet-clay